Movie-lovers can't get enough of 'Casablanca,' which may explain new talk about a long-planned sequel

For almost as long as there have been movies, there have been sequels. "The Godfather," "Star Wars," "The Lord of the Rings," the Twilight series—if there's anything Hollywood likes more than a blockbuster, it's the follow-up to one. Perhaps it's the dearth of original ideas or the desire among studios to cash in on a proven winner one more time (or two or three more times). So I can't say I was particularly surprised to learn, earlier this month, that there's talk of a sequel to that most storied of Hollywood productions, "Casablanca," which turned 70 on Thanksgiving Day.

Despite several earlier attempts that ultimately got the ax, the new sequel is actually an old one, written sometime in the late 1980s by Howard Koch, who shared the original film's 1943 Oscar for Best Screenplay with Philip and Julius Epstein. The script, "Return to Casablanca," chronicles the afterlives of the four principal characters. After making it safely to America, Ilsa Lund (originally played by Ingrid Bergman) and Victor Laszlo (Paul Henreid) attempt in vain to reconnect with resistance fighters Rick Blaine (Humphrey Bogart) and Captain Renault (Claude Rains) in North Africa. The script's main conceit is that Ilsa has a son from her relationship with Blaine and the boy grows up to be like his father, politically and otherwise.

'Humphrey Bogart and Ingrid Bergman in "Casablanca." "Casablanca" is a film that has come to represent, possibly more than any other picture, our most fundamental understanding of what movies should be and how they can affect us, writes Noah Isenberg. WARNER BROS / Ronald Grant Archi

In 1989, six years before his death, Koch's idea for the sequel was rejected by Warner Bros. But Cass Warner, granddaughter of studio co-founder Harry Warner, onetime writing student of Koch and head of her own independent production company, Warner Sisters, is determined to have the sequel made, as she recently announced on her website.

Whether or not "Return to Casablanca" ever gets made may be of less interest, however, than the fact that it is still being considered. Even this many decades after its release, "Casablanca" remains the go-to film for celebrations of Hollywood. It may not occupy the same mythical place it once did, but its mystique and cult status still endure.

Teaching a seminar devoted to the film this semester, I've been pleased to see my students respond the same way that audiences have since the premiere at New York City's Hollywood Theater 70 years ago. They laugh when Peter Lorre sidles into Rick's Café; they get misty-eyed during the singing of the Marseillaise; they cheer on Rick when he aids the Bulgarian couple trying to secure coveted exit visas; they express disbelief when Ilsa boards the plane with Laszlo; and they endlessly hum "As Time Goes By."

Amazingly enough, the film's composer Max Steiner, a Viennese-born musician who scored hundreds of Hollywood movies, was initially disinclined to use a popular song. Little did he know that his subtle, recurrent variations of the tune would sear it permanently in our collective imagination.

"Casablanca" has come to represent our most fundamental understanding of what movies should be and how they can affect us. Practically every story line plays directly to our common humanity. There's personal sacrifice for the greater good in Rick's relinquishing of Ilsa, the love of his life. There's an ugly truth about the inevitability of moral compromise, embodied by the shifty Renault. And there is an honest look at the noble if unglamorous path of Laszlo, following his convictions. It is the stuff of messy reality in every generation.

Then too, of course, there are the iconic performances. Although Bogart had already established his rugged screen persona in such films as "The Maltese Falcon" and "High Sierra," his portrayal of Rick offered a reprise with added complexity and vulnerability. Similarly, Bergman's Ilsa introduced the world to a stylish yet demure femininity—sex appeal without sex.

I recently interviewed Leslie Epstein, son of "Casablanca" screenwriter Philip Epstein, and he suggested another factor that makes the movie a perennial favorite. The picture, he said, remains the "archetype of how Americans would like to think of themselves—as tough ('I stick my neck out for nobody') but underneath there's a heart and they do the right thing." It's an idea that is as potent now as ever before. Whether that makes "Casablanca" ripe for a sequel, I don't know. I'll leave that to the executives in the front office.

—Mr. Isenberg, who directs the Screen Studies Program at the New School's Eugene Lang College, is working on a book about "Casablanca."

Corrections & Amplifications An earlier version of this article incorrectly said that the Bulgarian couple in "Casablanca" were trying to obtain letters of transit.

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